196 research outputs found
Oceans of Tomorrow sensor interoperability for in-situ ocean monitoring
The Oceans of Tomorrow (OoT) projects,
funded by the European Commission’s FP7 program, are
developing a new generation of sensors supporting physical,
biogeochemical and biological oceanographic monitoring.
The sensors range from acoustic to optical fluorometers to
labs on a chip. The result is that the outputs are diverse in a
variety of formats and communication methodologies. The
interfaces with platforms such as floats, gliders and cable
observatories are each different. Thus, sensorPeer ReviewedPostprint (author's final draft
A conformational RNA zipper promotes intron ejection during non-conventional XBP1 mRNA splicing.
The kinase/endonuclease IRE1 is the most conserved signal transducer of the unfolded protein response (UPR), an intracellular signaling network that monitors and regulates the protein folding capacity of the endoplasmic reticulum (ER). Upon sensing protein folding perturbations in the ER, IRE1 initiates the unconventional splicing of XBP1 mRNA culminating in the production of the transcription factor XBP1s, which expands the ER's protein folding capacity. We show that an RNA-intrinsic conformational change causes the intron of XBP1 mRNA to be ejected and the exons to zipper up into an extended stem, juxtaposing the RNA ends for ligation. These conformational rearrangements are important for XBP1 mRNA splicing in vivo. The features that point to such active participation of XBP1 mRNA in the splicing reaction are highly conserved throughout metazoan evolution, supporting their importance in orchestrating XBP1 mRNA processing with efficiency and fidelity
Developing tissue specific antisense oligonucleotide-delivery to refine treatment for Duchenne muscular dystrophy
Duchenne muscular dystrophy (DMD) is a severe progressive muscle wasting disorder. DMD is caused by reading frame disrupting mutations in the DMD gene resulting is an absence of the dystrophin protein. Dystrophin is an important muscle protein as it provide stability upon muscle fiber contraction. Currently there is no therapy for the majority of the DMD patients. As part of the standard of care patient receive symptomatic treatment e.g. corticosteroids, respiratory and cardiac support. Various therapeutic approached are currently under development. Most advanced therapeutic approach is aimed to restore dystrophin production by using antisense oligonucleotides (AON): exon skipping. This thesis focusses on delivery of AON to skeletal and cardiac muscle for DMD. With the help of phage display technology combined with next generation sequencing analyses, muscle homing peptides have been identified. In this thesis is described how for the first time these homing peptides upon conjugation to a 2OMePS AON resulted in increased delivery and exon skipping in a mouse model for DMD. In Conclusion, muscle homing peptides have the potential to facilitate delivery of AONs and perhaps other compounds to skeletal and cardiac muscle.
 Prinses Beatrix SpierfondsLUMC / Geneeskund
Radiation from polarized vacuum in a laser-particle collision
The probability of photon emission of a charged particle traversing a strong
field becomes modified if vacuum polarization is considered. This feature is
important for fundamental quantum electrodynamics processes present in extreme
astrophysical environments and can be studied in a collision of a charged
particle with a strong laser field. We show that for today's available 700 GeV
(6.5 TeV) protons and the field provided by the next generation of lasers, the
emission spectra peak is enhanced due to vacuum polarization effect by 30%
(suppressed by 65%) in comparison to the traditionally considered Compton
process. This striking phenomenon offers a novel path to the laboratory-based
manifestation of vacuum polarization.Comment: 6 pages, 1 figur
On the new and old physics in the interaction of a radiating electron with the extreme electromagnetic field
We show that an all-optical configuration of the laser-electron collision in
the configuration based on 10~PW-class lasers presents a viable
platform for reaching the range of parameters where a perturbative QED in
strong external electromagnetic field breaks. This case is contingently
referred to as a case of the nonperturbative QED; and this range of parameters
is the intriguing goal from an experimental point of view because of a possible
manifestation of a new physics of the interaction of a highly radiating
particle with a strong electromagnetic field. We show that the strong field
region can be reached by the electrons having the initial energy higher than 50
GeV. Our theoretical considerations are in agreement with three-dimensional
particle-in-cell simulations. While increasing of the electron energy raises
the number of electrons experiencing the strong field region, the observable
signature of photon emission radiative correction in the strong field is
expected to fade out when the electron energy surpasses the optimal value. This
threshold of electron energy is identified and the parameters for achieving the
nonperturbative limit of QED are provided.Comment: 6 pages, 2 figure
Applying OGC sensor web enablement to ocean observing systems
The complexity of marine installations
for ocean observing systems has grown significantly in
recent years. In a network consisting of tens, hundreds
or thousands of marine instruments, manual
configuration and integration becomes very
challenging. Simplifying the integration process in
existing or newly established observing systems would
benefit system operators and is important for the
broader application of different sensors. This article
presents an approach for the automatic configuration
and integration of sensors into an interoperable
Sensor Web infrastructure. First, the sensor
communication model, based on OGC's SensorML
standard, is utilized. It serves as a generic driver
mechanism since it enables the declarative and
detailed description of a sensor's protocol. Finally, we
present a data acquisition architecture based on the
OGC PUCK protocol that enables storage and
retrieval of the SensorML document from the sensor
itself, and automatic integration of sensors into an
interoperable Sensor Web infrastructure. Our
approach adopts Efficient XML Interchange (EXI) as
alternative serialization form of XML or JSON. It
solves the bandwidth problem of XML and JSON.Peer ReviewedPostprint (author's final draft
Highly Radiating Charged Particles in a Strong Electromagnetic Field
We consider highly radiating ultra-relativistic electrons in a strong
external electromagnetic field. High intensity radiative losses and consequent
-pair production, appearing in the frame of quantum electrodynamics,
determine indirectly mass operator of electrons in the strong field. We
calculate a leading term of the mass operator at asymptotically high energies
of electrons in a strong constant field. We do not use any perturbation theory
based on a low ratio of this mass operator to the electron mass , but only
the original small parameter of quantum electrodynamics, the fine structure
constant, . The analogous %but less nontrivial result is obtained for
the polarization operator for photon propagator. These results resolve at least
partially a very long-lasted controversy originating from traditional and
straightforward application of perturbative approaches for description of
highly radiating ultra-relativistic charged particles in a very strong
electromagnetic fields.Comment: 5 page
- …